This invention relates to motion sensing, and more particularly to novel method and apparatus by which the motion of a movable member is utilized to control one or more events associated with said movable member.
There are many industrial, commercial and other activities in which it is desirable to control the movement of a movable member. Exemplary of such activities is the operation of a lift truck in the transport of objects from one location to another. Because of the desire to achieve maximum productivity from the lift truck, it has become a general practice among operators thereof to utilize the transmission as a braking mechanism, by shifting the transmission to the opposite driving direction before the speed of movement of the vehicle has been reduced to an appropriate magnitude. The result of such operation is reflected adversely in the excessive costs incident to frequent breakdown of the vehicle, generally requiring replacement or repair of the transmission, and the loss of productivity from the vehicle during the time required for such replacement or repair.
Another example of an activity involving the control of movement of a movable member, is the maintenance of a predetermined movement of a conveyor, for example for the continuous delivery of specified numbers or amounts of objects or materials to subsequent processing stations.
Motion sensing and controlling devices for the foregoing and other activities have been provided heretofore. However, they are generally characterized by excessive degrees of inaccuracies, lack of reproducibility, and complex constructions reflecting excessive costs of manufacture, maintenance and repair.